Kumar Sunjeet, Wang Mengzhao, Liu Yi, Fahad Shah, Qayyum Abdul, Jadoon Sultan Akbar, Chen Yanli, Zhu Guopeng
Key Laboratory for Quality Regulation of Tropical Horticultural Crops of Hainan Province, School of Horticulture, Hainan University, Haikou, China.
Sanya Nanfan Research Institute, Hainan University, Sanya, China.
Front Plant Sci. 2022 Nov 10;13:1054924. doi: 10.3389/fpls.2022.1054924. eCollection 2022.
Nickel (Ni) contaminated soil is a persistent risk to plant growth and production worldwide. Therefore, to explore the Ni toxicity levels in sweetpotato production areas, we investigated the influence of different Ni treatments (0, 7.5, 15, 30, and 60 mg L) for 15 days on phenotype, Ni uptake, relative water content, gas exchange, photosynthetic pigments, oxidative stress, osmolytes, antioxidants, and enzymes of sweetpotato plants. The results presented that Ni at higher levels (30 and 60 mg L) substantially reduced growth, biomass, and root morphological traits. The Pearson correlation analysis suggested that Ni toxicity causes oxidative injuries as persistent augmentation of hydrogen peroxide (HO) and malonaldehyde (MDA) and reduced RWC, gas exchange, and photosynthetic pigment. Furthermore, this study revealed that sweetpotato could tolerate moderate Ni treatment (up to 15 mg L) by reducing oxidative stress. The results also indicated that the increase in the activities of mentioned osmolytes, antioxidants, and enzymes is not sufficient to overcome the higher Ni toxicity. Based on these results, we suggest using low Ni-contaminated soil for better growth of sweetpotato and also could be used as a phytoremediator in moderate Ni-contaminated soil.
镍（Ni）污染土壤对全球植物生长和生产构成持续风险。因此，为探究甘薯产区的镍毒性水平，我们研究了不同镍处理（0、7.5、15、30和60毫克/升）持续15天对甘薯植株表型、镍吸收、相对含水量、气体交换、光合色素、氧化应激、渗透调节物质、抗氧化剂和酶的影响。结果表明，较高水平（30和60毫克/升）的镍显著降低了生长、生物量和根系形态特征。Pearson相关性分析表明，镍毒性导致氧化损伤，表现为过氧化氢（H₂O₂）和丙二醛（MDA）持续增加，相对含水量、气体交换和光合色素降低。此外，本研究表明，甘薯可通过减轻氧化应激来耐受中度镍处理（高达15毫克/升）。结果还表明，上述渗透调节物质、抗氧化剂和酶活性的增加不足以克服较高的镍毒性。基于这些结果，我们建议使用低镍污染土壤以促进甘薯更好生长，并且甘薯也可作为中度镍污染土壤的植物修复剂。
